[bluGill]

They are still not harmless. They are normal. However if they are at all above natural (that is your input levels) you should treat and remove them. It is not unusual for the output of a sewage treatment plant to be cleaner water than what goes into your drinking water system.

[cyberax]

From a quick lookaround, it looks like a lot of water sources in the area have similar natural levels of arsenic. I could not find chromium content information, and it's plausible that it can be leached from stainless steel.

These are pretty much the only two concerning contaminants. Everything else in the report is just fear-mongering, like the BS about manganese.